Physicochemical Characterization of a Heat Treated Calcium Alginate Dry Film Prepared with Chicken Stock

• Published in: Journal of food science Vol. 82; no. 4; pp. 945 - 951
• Main Authors: Báez, Germán D., Piccirilli, Gisela N., Ballerini, Griselda A., Frattini, Agustín, Busti, Pablo A., Verdini, Roxana A., Delorenzi, Néstor J.
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01-04-2017
• Subjects: Alginates; Alginates - chemistry; Animals; calcium alginate; Calorimetry, Differential Scanning; chicken stock; Chickens; Color; Desiccation; Drying; edible film; Food Handling; Food science; Gelatin - chemistry; Gelatins; Gels - chemistry; Glucuronic Acid - chemistry; Heat treating; Heat treatment; Hexuronic Acids - chemistry; Hot Temperature; Maillard Reaction; Microscopy, Electron, Scanning; Peptides; physicochemical characterization; Poultry; Poultry Products; Raw materials; Spectroscopy, Fourier Transform Infrared; physicochemical characterization; calcium alginate; heat treatment; chicken stock; edible film
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/1750-3841.13658

Solid sodium alginate was dissolved into chicken stock in order to give a final alginate concentration of 0.9 percent (w/v). Calcium ions present in chicken stock were enough to induce ionic gelation. After drying, Fourier transform infrared spectroscopy, thickness and mechanical properties of films obtained were determined. Calcium alginate‐chicken stock films were heated at 130 °C for different times between 0 and 15 min. Mechanical and optical studies, differential scanning calorimetry, visual aspect and scanning electron microscopy were carried out to describe physicochemical properties of heat treated films. Heating developed a maroon ochre color and increased the brittleness (crispness) of the films related to the intensity of the treatment. Differential scanning thermometry and study on appearance of the films suggested that Maillard reactions may be responsible for the observed changes. Maillard reactions mainly occurred between reducing sugar monomers and free amino groups of gelatin peptides present in the chicken stock, and between alginate and gelatin peptides to a lesser extent. In addition, the plasticizing effect of fat added with chicken stock was also studied. These studies suggest a potential use of heat treated chicken stock films as a substitute of roasted chicken skin.
Practical Application
Crisp texture and optical properties of heat treated calcium alginate‐chicken stock films obtained in this work were similar to roasted chicken skin. Therefore, this information can be used by product developers, culinary scientists and professional chefs in designing food products in which these kinds of films are employed to wrap chicken meat pieces that are then subjected to cooking. This study provides the basis for the preparation of healthier alternatives to traditional roasted skin through reduction dangerous components, such as fat (including cholesterol) and carcinogenic compounds, without loss of overall flavor intensity.